Synthesis and infrared characterization of Br-HBr and Br-DBr entrance channel complexes in solid parahydrogen.
We report high resolution vibrational spectra in the HBr (2560 cm(-1)) and DBr (1840 cm(-1)) stretching regions for Br-HBr and Br-DBr entrance channel complexes isolated in solid parahydrogen (pH2). The Br-HBr complexes are generated by synthesizing solid pH2 crystals doped with trace amounts of HBr/Br2 mixtures followed by 355 nm in situ photodissociation of Br2 to form Br atoms. After photolysis is complete, the solid is warmed from 2 to 4.3 K resulting in the irreversible formation of Br-HBr complexes. The large 36.63 cm(-1) HBr monomer-to-complex induced vibrational shift to lower energy measured in these studies is consistent with the linear Br-HBr hydrogen bonded structure predicted from theory. The 0.02 cm(-1) Br-HBr absorption linewidths indicate a 1 ns vibrational excited state lifetime for these entrance channel complexes in solid pH2.
Kettwich
Sharon C
SC
Department of Chemistry, University of Wyoming, Laramie, Wyoming 82071, USA.
Pinelo
Laura F
LF
Anderson
David T
DT
D001966:Bromine / Q000737:chemistry* / Q000528:radiation effects; D003080:Cold Temperature; D003903:Deuterium / Q000737:chemistry* / Q000528:radiation effects; D018054:Hydrobromic Acid / Q000138:chemical synthesis* / Q000737:chemistry* / Q000528:radiation effects; D006859:Hydrogen / Q000737:chemistry* / Q000528:radiation effects; D006860:Hydrogen Bonding; D010782:Photolysis; D017550:Spectroscopy, Fourier Transform Infrared / Q000295:instrumentation / Q000379:methods; D014466:Ultraviolet Rays; D014732:Vibration
D018054:Hydrobromic Acid; D006859:Hydrogen; D003903:Deuterium; D001966:Bromine